Flat rolled products in the metals industry are commonly wound into coils. These coils are transported by coil conveying systems such as roller chain conveyors and walking beam conveyors.
The roller chain conveyors are comprised of a plurality of individual coil support pallets linked together by chain sections. Wheels mounted on bearings and axles support each pallet. Roll chain conveyors are generally driven by sprockets mounted on a rotating shaft. The rotating shaft is driven by a gear reducer and motor. The roller chain conveyor is guided by custom-machined track which is supported on structural steel. The disadvantages of this design are: 1) there are a lot of parts to maintain since each pallet has rollers, bearings and axles; 2) the chain stretches, which affects the positioning of the downstream coil; 3) the custom-machined track wears out due to the high load of the roller (wheel); 4) the individual components are difficult to repair; 5) the system is costly due to the number of component parts and the need for custom track; and 6) the conveyor speed is limited.
Walking beam conveyors are comprised of a multitude of coil support pallets mounted on a beam. The beam is supported on rollers. The conveyor indexes coils between stationary coil support saddles. The conveyor includes an elevating mechanism which lifts the coils up off of stationary saddles. The conveyor is then traversed, to index the coils to adjacent saddles downstream. The conveyor is usually driven by a hydraulic cylinder. The disadvantages of this design are: 1) the distance of traverse of the walking beam is limited by the length of the cylinder stroke, 2) the length of the beam conveyor is limited by manufacturing and shipping constraints, 3) the speed of the conveyor is limited by the operating speed of the drive cylinder, and 4) repairing the walking beam support rollers and elevating mechanisms requires major disassembly of the unit because the rollers and elevating mechanisms are fixed on foundations.
Accordingly, the present invention seeks to improve upon the previous apparatuses by providing a shuttle car conveyor comprising a plurality of individual cars. Each individual car of the shuttle conveyor is coupled to an adjacent individual car of the shuttle conveyor. A spacer couples the individual cars to positively space the cars a fixed distance during movement of the shuttle between a first position and a second position.
The shuttle car conveyor has several advantages. Connecting the cars to keep the cars a fixed distance apart when the shuttle is driven from the first position to the second position facilitates accurate positioning of the coils by the shuttle car conveyor. The fixed spacing also simplifies automation because the shuttle car conveyor can operate with only a single car having a drive mechanism.
Additionally, providing a shuttle car conveyor made up of individual cars simplifies maintenance. The cars can be easily disassembled and repaired as separate modules. Further, providing individual cars allows the shuttle to continue operating even if one of the car's motors is not functioning.
The shuttle car conveyor can be easily adapted to various systems. The shuttle car conveyor can be lengthened by adding car modules or spacers, or by lengthening the spacers. The shuttle car conveyor design allows for the use of standard rails. The option of using either electric motor, hydraulic motor or cable drum drive to power the shuttle allows the shuttle to operate at higher speeds than the chain conveyor system or walking beam conveyor system.